The present invention is directed to a contact adhesive useful for adhering a variety of materials to a variety of substrates. The contact adhesives of the present invention are substantially or entirely free of organic solvents since they are aqueous dispersions of polyacrylates.
Various adhesives are formulated for use as contact cements. The most useful member of the particular class of adhesives are the solvent based contact cements. The use of these cements results in the release of toxic and flammable solvents into the environment. These materials are difficult to apply and clean up, unstable in the container, subject to solvent loss and phasing out of the non-volatile content of such adhesives. These adhesives tend to crystalize and discolor at sustained temperatures above 150.degree. to 160.degree. F.
A second type of contact adhesive which has recently been introduced is the aqueous dispersion type contact adhesives. The aqueous dispersion type contact adhesives of the prior art however, have less than the desirable degree of bond strength, resistance to heat and oxidation, stability in containers, and freeze-thaw stability generally. Specific types of aqueous dispersion type contact adhesives cause eye irritation, have an unpleasant odor, are difficult to apply because they are too free-flowing, and are difficult to clean up after use. The prior art adhesives include neoprene and natural rubber dispersions in water.